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Split (explode) pandas dataframe string entry to separate rows
I have a pandas dataframe in which one column of text strings contains comma-separated values. I want to split each CSV field and create a new row per entry (assume that CSV are clean and need only be split on ','). For example, a should become b :
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Fast Bitmap Blur For Android SDK
Currently in an Android application that I'm developing I'm looping through the pixels of an image to blur it. This takes about 30 seconds on a 640x480 image.
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What's the best practice to round a float to 2 decimals? [duplicate]
I'm using eclipse + Android SDK.
7 Answers
7
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Is there a performance gain in using single quotes vs double quotes in ruby?
Do you know if using double quotes instead of single quotes in ruby decreases performance in any meaningful way in ruby 1.8 and 1.9.
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Truncate number to two decimal places without rounding
Suppose I have a value of 15.7784514, I want to display it 15.77 with no rounding.
36 Answers
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What's the fastest way to merge/join data.frames in R?
For example (not sure if most representative example though):
5 Answers
5
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Can a class member function template be virtual?
I have heard that C++ class member function templates can't be virtual. Is this true?
12 Answers
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How to plot two histograms together in R?
I am using R and I have two data frames: carrots and cucumbers. Each data frame has a single numeric column which lists the length of all measured carrots (total: 100k carrots) and cucumbers (total: 50k cucumbers).
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How do I plot in real-time in a while loop using matplotlib?
I am trying to plot some data from a camera in real time using OpenCV. However, the real-time plotting (using matplotlib) doesn't seem to be working.
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Moving decimal places over in a double
So I have a double set to equal 1234, I want to move a decimal place over to make it 12.34
9 Answers
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